Kingspan Light + Air Skylights: KT11 vs KT12, ULSV Smoke Vents and Safety Screens

The Kingspan Light + Air dome skylights we carry come from two families: KS11 and KT11 are Series 1100, and KT12 is Series 1200. We also carry Kingspan's ULSV smoke vents and the SSCRN screens and SCAGE cages that protect those openings. This guide explains the differences, the model codes and the screen rules, using only our listings and the Kingspan documents posted on them.

Series 1100 vs Series 1200

	Series 1100 (KS11, KT11)	Series 1200 (KS12, KT12)
Frame	KS11 is not thermally broken. KT11 is thermally broken	KS12 is the standard frame. KT12 is thermally broken
Dome	KAT dome on our listings, ridged to collect low angle daylight	Triarch dome in Kingspan's specification, also ridged
Standard sizes	24 to 60 inches wide, 36 to 120 inches long	24 to 72 inches wide, 24 to 120 inches long
FM Approval	Single and double dome configurations only (FM 4431)	Not stated on the data sheet
What we list	4848 and 4896 KT11 (triple glazed), 4896 KS11 (single glazed)	Two 4689 KT12 units (double glazed)

Both families offer single, double or triple glazing, a 6:12 maximum slope and a 10 year warranty that covers leaks and documented hail stones 2 inches or smaller, with exceptions. A thermal break separates the exterior frame from the interior frame, which Kingspan's installation guide ties to lower condensation risk, so choose a KT model over heated or air conditioned space.

Series 1100 glazing and energy values

Model	Glazing, outer to inner	U-factor	SHGC	VLT
4848 and 4896 KT11 CT 3 WPC WPP C16 MF	White polycarbonate, white prismatic, clear 16 mm multi-wall	0.44	0.37	0.27
4848 and 4896 KT11 CT 3 WPC CPP C16 MF	White polycarbonate, clear prismatic, clear 16 mm multi-wall	0.44	0.40	0.29
4896 KS11 CT 1 WPC MF	White polycarbonate, single glazed	1.38	0.67	0.63

Going from the single glazed KS11 to a triple glazed KT11 drops the U-factor from 1.38 to 0.44, so the KT11 is the pick when the energy code sets a skylight U-factor. The trade is light: visible transmittance falls from 0.63 to 0.27 or 0.29. The clear prismatic (CPP) middle layer passes slightly more light and heat than the white prismatic (WPP) layer. One catch: FM Approval covers single and double dome Series 1100 units only, not the triple glazed KT11, so tell us if the roof insurer requires FM.

The 4689 KT12

4689 is not a standard Series 1200 size; Kingspan's drawing notes that custom sizes are available. Both units we list are thermally broken and double glazed: the 4689 KT12 CMT 2 CPC WPP MF has a clear outer dome over a white prismatic inner dome, and the 4689 KT12 CMT 2 WPC O16 MF has a white outer dome over a 16 mm multi-wall panel, with a listed U-factor of 0.49. Send us measured curb dimensions and we will confirm the fit before ordering.

How to read a Kingspan skylight model number

Our listing 4896 KT11 CT 3 WPC WPP C16 MF is the same unit Kingspan writes as 4896-KT11-CT-3-WPC/WPP/C16-MF.

Segment	Meaning
4896	Model size. A 4896 is 48 x 96 inches at the rough opening and inside the curb
KT11	Series and frame: KS11 or KT11 for Series 1100, KS12 or KT12 for Series 1200. T means thermally broken
CT	Base. CT or CMT: curb mount with EPDM foam seal tape. CM: curb mount, sealed in the field. SF: self flashing
3	Number of glazing layers
WPC/WPP/C16	Glazing, outer to inner. WPC or CPC: white or clear polycarbonate. WPP or CPP: white or clear prismatic. C16: clear 16 mm multi-wall panel
MF	Mill finish. Anodized and painted finishes are also offered

Sizes and curb fit

Size	Rough opening and inside curb	Outside curb	Series 1100 inside frame	ULSV inside frame
4848	48 x 48 in	51 x 51 in	52.5 x 52.5 in	52.25 x 52.25 in
4896	48 x 96 in	51 x 99 in	52.5 x 100.5 in	52.25 x 100.25 in

The frame drops over the curb, so the outside curb dimension is the number that has to match, with 1/2 to 3/4 inch of clearance for the roofing to terminate under the frame. Kingspan's Series 1200 drawing says to measure the outside of the curb and then corner to corner, because a curb too far out of square will not fit. Its installation guide warns against lapping roofing over the curb top, skipping predrilled holes, and setting the skylight flat on the roof.

ULSV smoke vents

The ULSV is Kingspan's Series 3100 smoke vent, listed to UL 793. Spring loaded doors are latched shut until a fusible link releases them, they open against a 10 psf uniform load, and every unit has an exterior manual release. Sizes are 4848, 4872, 4896 and 6072, with A for an aluminum frame or S for galvanized steel. All four we list are aluminum 4896 units for a 51 x 99 inch curb:

• 4896 A ULSV CMT 1 WPC 370: single glazed white
• 4896 A ULSV CMT 2 CPC WPP 370: double glazed, clear over white prismatic
• 4896 A ULSV CT 1 WPC 360: single glazed white, 360 degree link
• 4896 A ULSV LV CT 1 WPC 360: drawn by Kingspan on a vortex venting base

Smoke vents are preloaded with high tension springs, so remove the shipping straps after installation or the vent will not work as designed, and never stand over the doors while the straps come off or during testing.

The 5596 and 55102 ASLDOUL are Series 3500 dropout vents, also listed to UL 793. Their acrylic domes are designed to drop out when exposed to the UL fire test, and an aluminum adaptor frame fits existing roof curbs. Our listings describe the T4896 SSV and SSVLV as non-listed torsion spring smoke hatches.

SSCRN safety screens vs Gladiator SCAGE cages

	SSCRN safety screen	SCAGE external cage
Where it goes	Inside the curb, under the unit	Outside, over the dome, fastened to the skylight frame
Wire	0.162 inch galvanized steel, 4 inch grid	1/4 inch nominal galvanized steel, 4 inch square grid
Fastening	To the curb, no more than 8 inches apart	#8 TEK screws to the frame, no more than 12 inches apart
Use with	Skylights and operable smoke vents	Skylights and dropout (melt-out) vents
Sizes we list	4848, 4872, 4896, 6060, 6072, 6096, 4689	3648, 4896, 5596, 55102

Both carry the Gladiator name, are sized by inside curb dimension, have a 10 year warranty, and are stated on their data sheets to meet OSHA CFR load values. The rule that matters most: operable smoke vents such as the ULSV take interior screens only, and dropout vents take exterior cages only. Kingspan also recommends fall restraint systems and an annual inspection of every skylight and smoke vent. For the code background, see OSHA fall protection for skylights.

FAQ

Which Kingspan skylights are thermally broken?

Models with a T in the code: the KT11 and KT12. The KS11 is not.

Is the triple glazed KT11 FM Approved?

No. The Series 1100 data sheet limits FM Approval to single and double dome units.

Can I put a Gladiator cage over a ULSV smoke vent?

No. Operable smoke vents take an interior SSCRN screen only.

Next steps

Every unit above is on our Kingspan Light + Air brand page, with data sheets on the skylight and smoke vent spec sheet pages. For matching curbs, see our AES and Curbs Plus curb guides. Send the quantity, model and curb dimensions through the skylight, smoke vent or fall protection request for quote page, and we will confirm the fit before Kingspan builds it.